17 Study of Mycobacterium Tuberculosis by Molecular Methods in Northeast Mexico H. W. Araujo-Torres 1,3 , J. A. Narváez-Zapata 2 , M. G. Castillo-Álvarez 1 , MS. Puga-Hernández 4 , J. Flores-Gracia 5 and M. A. Reyes-López 1,* 1 Conservation Medicine Lab., Centro de Biotecnología Genómica del Instituto Politécnico Nacional, Cd. Reynosa, Tamps, 2 Industrial Biotechnology Lab., Centro de Biotecnología Genómica del Instituto Politécnico Nacional, Cd. Reynosa, Tamps, 3 Centro de Investigación en Ciencia Aplicada y Tecnología Avanzada del Instituto Politécnico Nacional, Altamira, Tamps, 4 Laboratorio Estatal de Salud Pública de Tamaulipas, Cd. Victoria, Tamps, 5 Instituto Tecnológico de Ciudad Victoria, Cd. Victoria, Tamps México 1. Introduction One third of the world population is afected by TB and one million people did die this year 2011 in undeveloped countries (Venkatesh et al., 2011). In Tamaulipas, a Northern State of Mexico and a border state between USA and Mexico, frequency is 26.9 new TB cases per 100,000 people, twice of national rate of 12.85 cases per 100,000 people (Ferrer et al., 2010). Only on the border of Tamaulipas about 320 cases are diagnosed each year. Many of these cases correspond to people from other states of Mexico, probably by geographic position and by migration problematic of this study zone (Fitchett et al., 2011). Only 92% of the treated population are cured mainly because much of these people are poor and whose nutritional status directly affects the possibility of quick recovery (SSA, 2009). The long presence of this disease has increased the need to know specifically which Mycobacterium tuberculosis strains are circulating in the region. Additionally, it is necessary to know the antibiotic/susceptibility profile of these strains since many of them acquire resistance against the traditional antibiotics along time. In general, the diagnostic of this disease is traditionally conducted by using gold standard techniques focused to identify the presence of M. tuberculosis in clinical specimen of humans or cattle. These techniques included the strain of microorganism in Ziehl-Neelsen and culture in Lowenstein-Jensen medium (Cadmus et al., 2011), both regarded as reference techniques in the diagnosis of TB. Differentiation among mycobacteria of the M. tuberculosis complex (MTC) and other than MTC (NMTC) is accomplished by applying biochemical tests: niacin production, catalase activity, thermostable at 68 ° C and reduction of nitrate. * Corresponding Author www.intechopen.com